Fleas are important to pet owners because they are the most common parasitic skin infection of dogs and cats and therefore cause more skin diseases than any other parasite.
But while skin disease and irritation from flea bites are the most common symptoms of a flea infestation, they can also be the vector for diseases like tapeworms, which can cause anal irritation in affected dogs and cats. Therefore, flea treatment and an effective control strategy are important because if they are still the most common parasitic skin diseases, we are in a sense not winning the battle.
I don’t want to get into any cat vs. dog debate, but within the world of fleas, the cat flea Ctenocephalides felis (the first ‘C’ is dumb) has generally won the war for dominance over cats and dogs. If a survey of a pet population is carried out, it is likely that some dog fleas will be found, and particularly in remote areas, but this is rare and their numbers are much lower than their cat counterparts. But then I suppose one could also argue that actually the terms cat and dog fleas are a bit irrelevant, just because a scientist long ago named a particular species C. felis, doesn’t mean it’s a ‘cat flea’. rather than C. canis it belongs to dogs.
Of course, cats and dogs are not only infected with their own species, there are also other species such as: Pulex irritans, the human flea; Leptosylla segnis the mouse; Spilopsyllus cuniculi the rabbit flea; and Echidnophaga gallinacea, the chicken or ‘sticker’ flea. The common name of the sticky flea derives from the fact that when biting a host, it actually attaches itself permanently using its mouthparts. This allows it to remain attached to the pet (or chicken) long after an effective treatment has killed it; this may give the wrong impression that the control product did not work effectively.
Another infamous flea is the oriental Xenopsylla cheopis. This is the flea responsible for causing so much fear in human populations in times past because it is the vector (along with the rat) of the bubonic plague or Black Death, a bacterium called Yersinia pestis that is transmitted by flea bites. Naturally, the rat flea would prefer to infest rats, but when rats are in close contact with humans, there is a potential for the infestation to spread.
Okay, so talking about the plague doesn’t scare you too much because the last time the plague occurred was in an Albert Camus novel of the same name. But there are other still nasty zoonotic infections that fleas spread.
So-called ‘cat scratch fever’ is caused by a bacterium, Bartonella henselae, which is transmitted between cats by fleas. The bacterium is transmitted in flea feces, which is the likely source of contamination of cats’ claws during grooming. It is estimated that in the US about 2,000 of the 24,000 people infected each year require hospital treatment for the infection.
Another disease that veterinary scientists are investigating is a condition called “flea-borne spotted fever,” or cat flea typhus, which is caused by a bacterium called Rickettsia felis. Interestingly, the research seems to indicate that while the bacteria is present in fleas, it has not been detected in cats. Signs in humans include rash, headache, and central nervous system involvement, with some patients reporting nausea, vomiting, diarrhea, and abdominal pain. Feline flea typhus would certainly not be the most pleasant way to spend a few days.
I hope I have convinced you that it is vitally important to maintain effective flea control. Consult your vet or pet store for an appropriate flea treatment product for your pets.